Over the last 25 years, since about 1980, international co-operation in research on small pelagic schooling fish with pelagic eggs, such as anchovy, sardine, sprat, and sardinella focused, first on processes determining recruitment variability and, then, since the mid 1990s, on the impact of climate variability on ecosystems dominated by small pelagics. Recruitment research was carried out to a large extent under the umbrella of the Sardine–Anchovy– Recruitment Program (SARP) within the Ocean Science in Relation to Living Resources Program (OSLR) run jointly by IOC and FAO and the Climate and Eastern Ocean Systems project (CEOS) conducted by a variety of research institutions.

Lack of scientific understanding of the mechanisms regulating recruitment was widely recognized in the 1980s (and still is) as the key unsolved scientific problem currently hindering effective management of small pelagic fish populations. Their collapses such as the Californian sardine or the Peruvian anchovy have had enormous negative economic and social effects on fishing nations which might have been avoided had there been the opportunity to predict recruitment. Consequently, several international and national initiatives were started in the 1980s to understand the relationship between environmental processes and fish recruitment. At this point, Reuben Lasker's “stable ocean hypothesis” (Lasker, 1975, 1978) had suddenly caught the attention of the fisheries scientific community, and provided a major conceptual basis for motivating and planning the early activity. Simultaneously, two new technologies, the “Daily Egg Production Method” (DEPM) (Lasker, 1985) and a technique for daily age and growth estimates based on measuring and counting daily marks laid down on larval fish otoliths (Methot, 1983), were under development in Lasker's laboratory.